Requirements to run a 1jz head on NA mkiv

[Guest 97whtmkiv]

Hi all,

 

I have an 2jz-ge Mkiv supra and was wondering what is required to run a 1jz head? can you retain the stock 2jz ecu and loom or will the 1jz ecu be needed and a custom loom made up?

I want to do this swap as over here in Australia 1jz heads are extremely cheap and would allow the use of coil packs and cheaper manifolds/intakes etc.

when the head goes on i will also go single turbo instead of the stock 1jz twins.

 

Any input would be appreciated.

Thanks

[Mike2JZ]

You could probably re-use the 2JZGE engine loom, but it will take some effort and re-wiring/pinning to get it to work with a 1JZ ECU or even a 2JZGTE ECU, as you will need to remove and add sensors to the loom. I wouldn't attempt this unless you are confident with your wiring abilities and fancy a challenge.

 

It is far easier to run a 1JZ ECU & 1JZ engine loom, then adapt 10-20 wires to work with the JZA80 Supra interior plugs.

 

You cannot use your 2JZGE ECU as it does not have the maps required to operate under boost. 1JZ ECU would be my recommendation due to the stock 1JZ twins functioning like a small single turbo, unlike the 2JZGTE ECU where it's fuel/ignition maps are setup for sequential twins, which won't be ideal if you are planning to go single (unless you have some sort of fuel controller to somewhat counteract this)

[Guest 97whtmkiv]

what are the 10-20 wires that need adapting to run the 1jz loom and ecu? I am competent mechanically but have never done any wiring as such.

[Mike2JZ]

On the 1JZ loom, you will have 4 grey plugs for the ECU (if using a soarer loom, I think chaser and mkiii 1JZ's have white ecu plugs). These can remain as are and plug straight into the ECU.

 

There are also some additional plugs which plug into the interior loom of whatever vehicle the loom came from. These plugs need to be cut and the wires need to be re-wired into the Orange and grey plugs on mkiv supra interior loom. You can cut the orange and grey female plugs from the 2JZGE loom and attach the 1J wires to them.

 

For pinouts on what wire does what, check out:

 

Wilbro666 2JZGE

Wilbro666 1JZGTE (Soarer)

 

There are also a number of guides and thread out there about doing the above if you google around a bit

[Mike2JZ]

Also worth noting, that with a 1.5J it will run on a stock ECU, but a standalone ECU is the only way the you will get the most out of the setup. Everything else will always be a bit of a compromise.